CORE ABSTRACT The purpose of the Bioanalytical Core is to provide analytical capability for Projects #1-4 in human subjects and murine models of sepsis, including genomic, biochemical, and cell-functional analysis of isolated leukocyte populations, plasma, and tissue(s) of interest (e.g., skeletal muscle). The Core will: 1) characterize leukocyte populations phenotypically; 2) measure acute-phase protein, plasma cytokine, and select growth factor concentrations; 3) obtain a consistent genome-wide and gene-specific expression analysis profile from enriched cell populations and tissues; 4) assess protein catabolism and mitochondrial bioenergetics in muscle tissues by measuring mitochondrial function, reactive oxygen species, and catabolism-atrophy related pathways; and 5) provide a central scientific analysis platform for all projects. Aim 1. To phenotype blood and tissue leukocytes from humans and murine models of sepsis. We will focus on early myeloid cell populations derived from whole blood in humans with sepsis, and from bone marrow and spleen in mice with sepsis. Aim 2. To provide plasma or serum acute-phase protein, cytokine, and growth factor concentration measurements for clinical and laboratory studies using Luminex xMAP technology and ELISA. We will use a MILLIPLEX Analyzer 3.1 xPONENT System and standard ELISA microplate readers. Aim 3. To determine genome-wide and individual gene expression in both human and murine leukocytes and select tissue samples. We will assess exon-level, genome-wide expression with Affymetrix GeneChip(R) technology (HH/2) and determine expression of selected leukocyte genes by nanoString nCounter(R). Aim 4. To assess catabolism, bioenergetics, and select pathways of atrophy with novel and standard methodologies. The methodologies will allow us to better understand molecular and biochemical changes related to muscle atrophy and energy decline in human subjects and murine models. Aim 5. To develop innovative new methodologies and provide a central scientific platform for future discovery. The Core will collaborate with all projects for the integration of dynamic scientific knowledge and discovery and decide on newly innovative methodologies for future analysis. Additionally, the Analytical Studies Core will centralize the analytical capabilities that require sophistication and quality assurance beyond that available to individual projects. It will assure accuracy and standardization of complex analytical protocols that will be cost-efficient for the P50 Center.